sys/console: Disable blocking console on autocompletion
sys/console: Disable blocking console on autocompletion

If asynchronous UART RX is enabled, we do not need to set console to
blocking mode when doing autocompletion.

mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core